Hydrodynamic converter for a wind turbine

Abstract

The present invention relates to a novel hydrodynamic converter for a wind turbine (100) for generating electrical energy, comprising a pump (1) with a pump shaft (23) which can be mechanically connected to a rotor shaft (120a) of the wind turbine (100), a turbine (11) with a turbine shaft (45) which can be mechanically connected to a drive shaft (140) of a generator (130), and which is fluidically connected to the pump (1), wherein the hydrodynamic converter is configured to circulate hydraulic fluid in a circuit between the pump (1) and the turbine (11) and thereby transmit drive quantities of the pump shaft (23) to the turbine shaft (45).

Description

[0001] The present invention relates to a novel hydrodynamic converter for a wind turbine.

[0002] Automatic transmissions for motor vehicles are known in the prior art, which have a hydrodynamic torque converter that is usually arranged between the engine and transmission of a motor vehicle.

[0003] For example, EP 2 146 115 A1 discloses a hydrodynamic torque converter comprising a fluid-filled casing, a pump impeller mounted on the casing, a turbine impeller opposite the pump impeller and mounted in an interior space of the casing, and a guide vane arranged between the pump impeller and the turbine impeller. In converter operation of the torque converter, guide vane blades are arranged between the blades of the pump and turbine impellers such that fluid circulation between the turbine impeller and the pump impeller flows around the guide vane blades.

[0004] The present invention aims to provide a hydrodynamic converter for a wind turbine, which can extend the service life of the wind turbine and increase its efficiency.

[0005] The hydrodynamic converter according to the invention comprises a pump with a pump shaft and a turbine with a turbine shaft. The pump shaft is mechanically connectable to a rotor shaft of the wind turbine, and the turbine shaft is mechanically connectable to a drive shaft of a generator of the wind turbine. At least one rotor with one or more rotor blades can be arranged on the rotor shaft of the wind turbine, onto which wind force can be applied to drive the rotor. The generator can be an asynchronous or synchronous generator with a fixed or variable speed.

[0006] The mechanical connections between the individual shafts can be achieved, for example, by means of suitable couplings, such as rigid couplings, flexible couplings, or articulated couplings. It is also possible to arrange a gearbox, such as a mechanical gearbox, between the rotor shaft and pump shaft and / or between the turbine shaft and generator shaft.

[0007] Furthermore, the turbine is fluidically connected to the pump, i.e., an output of the pump is connected to an input of the turbine and an output of the turbine is connected to an input of the pump.

[0008] The hydrodynamic converter is designed to circulate hydraulic fluid in a circuit, particularly a closed circuit, between the pump and the turbine, thereby transmitting drive variables from the pump shaft to the turbine shaft. These drive variables include, for example, rotational speed, torque, and power. The hydraulic fluid can be, for instance, a hydraulic fluid such as a mineral oil-based or water-based fluid.

[0009] In particular, the pump shaft can be driven by the rotor shaft of the wind turbine at a specific speed and torque, whereupon the pump delivers hydraulic fluid to the turbine at a specific pressure. As a result, the turbine performs a rotary motion and drives the generator shaft via the turbine shaft. The closed hydraulic fluid circuit can be formed by the pump conveying the hydraulic fluid from the pump outlet, through the turbine inlet, into the turbine, and from there back through the turbine outlet and pump inlet to the pump.

[0010] The pump and turbine can each have a housing containing the corresponding inlets and outlets. Furthermore, the pump and turbine shafts can be supported in their respective housings by suitable bearings. The housings can be designed in two parts to facilitate easy assembly of the pump and turbine. The two housing parts of the pump or turbine housing can, for example, be bolted together. Any other suitable connection between the two housing parts is also possible.

[0011] In one embodiment of the hydrodynamic converter, a first hydraulic connection can be arranged between the pump outlet and the turbine inlet, and a second hydraulic connection between the turbine outlet and the pump inlet. The two hydraulic connections can be designed, for example, as lines and / or pipes.

[0012] In another embodiment of the hydrodynamic converter, the pump can have a rotor mounted on the pump shaft, with one or more vanes attached to its outer surface. Preferably, the rotor has two vanes; however, it is equally possible for only one vane or more than two vanes to be attached to the outer surface of the rotor. The outer surface of the rotor refers to its radial outer surface, the side facing away from the pump shaft. The rotor can be rigidly connected to the pump shaft, for example, by means of a suitable shaft-hub connection. It is also possible for the pump shaft and the rotor to be formed as a single piece.

[0013] In a preferred embodiment of the hydrodynamic converter, a rear (upstream) side of each vane can extend radially outward perpendicular to the outside of the rotor, and a front (downstream) side of each vane can extend at an angle from the outside of the rotor to an outer edge of the rear side. This allows each vane to have the shape of a right-angled triangle in a longitudinal section through the pump.

[0014] In one embodiment of the hydrodynamic converter, the pump can include a recirculating channel concentric to the drive shaft, connecting the pump's inlet and outlet. Additionally, the pump can have a barrier channel located between the pump's inlet and outlet, which is closed by a valve.

[0015] Advantageously, the circulation channel and the barrier channel can be arranged in the pump housing.

[0016] The bypass channel can have a circular arc shape and be designed such that the central angle of one of the circular arcs underlying the shape of the bypass channel lies in a range between 30° and 180°, with this central angle typically being 180°. In particular, the bypass channel can be arranged parallel to a plane perpendicular to an axis of the pump shaft in the pump housing.

[0017] In one embodiment of the hydrodynamic converter, the pump inlet can be configured to introduce the hydraulic fluid into the circulation channel in a tangential direction to a circle concentric with the pump shaft. Likewise, the pump outlet can be configured to discharge the hydraulic fluid from the circulation channel in a tangential direction to the circle concentric with the pump shaft. Hydraulic fluid entering the circulation channel tangentially through the pump inlet can exert pressure on the rear surfaces of the impellers located within the circulation channel, thus causing rotation of the rotor or pump shaft in the direction of flow of the hydraulic fluid. After circulating in the circulation channel, the hydraulic fluid can exit the pump tangentially through the pump outlet. This can occur, in particular, with a constant torque and with a tangential effect; that is, the flow direction of the hydraulic fluid can be tangential to the circular arc shape at any point in the circulation channel.In other words, the tangential effect can exist at any point during the entire circulation of the hydraulic fluid in the circulation channel, thereby achieving a high pump efficiency.

[0018] Preferably, the circulation channel is part of an annular, concentric channel formed around the rotor or pump shaft, which has openings for the pump inlet and outlet as well as the shut-off channel. The valve in the shut-off channel prevents hydraulic fluid located in the area of ​​the pump outlet from flowing back to the pump inlet. This prevents a "short circuit" with respect to the hydraulic fluid circulating in the pump. For this purpose, the valve can have a closing element that closes off a cross-section of the shut-off channel. The closing element can, for example, be a cylinder.

[0019] The entire channel can have a uniform diameter around its circumference, allowing the vanes to extend outwards in the same way in the bypass channel as in the circulation channel. In a preferred embodiment, the diameter of both the bypass channel and the bypass channel can be substantially equal to the length of the vane's trailing edge. In other words, the radial distance or circumferential gap between the outer edge of the vane trailing edges and the pump housing can be such that the vanes just barely do not touch the housing. Different boundary conditions at various operating points of the hydraulic converter can be taken into account when determining the required radial distance. This minimizes pump leakage and thus increases its efficiency.

[0020] According to another preferred embodiment of the hydrodynamic converter, a section of the sealing channel located between the valve and the pump outlet can be connected to the pump outlet by means of a bypass channel. This allows hydraulic fluid located between the front face of a vane entering the sealing channel and the valve's closing element to be directed to the pump outlet. This prevents hydraulic fluid from accumulating in the sealing channel upstream of the valve, which would otherwise impede or even completely prevent the freewheel from rotating.

[0021] In one embodiment of the hydrodynamic transducer, each vane can be configured to open the valve when it passes through the sealing channel. In particular, in this case, the valve's closing element can be pushed from a closed position to an open position by means of the inclined front face of the vane. The sealing channel can then be closed by the vane when the valve is open, as the vane extends over a diameter of the sealing channel. The valve can include a compression spring, against whose spring force the vane opens the valve and which closes the valve again once the vane has passed through the valve. Instead of a compression spring, the valve can include a solenoid for closing the valve. Specifically, the compression spring or the solenoid can act on the closing element, pushing it into a position where it closes the sealing channel.

[0022] According to one embodiment of the hydrodynamic converter, the turbine can be identical in construction to the pump, meaning the turbine can have the same elements with the same properties as the pump. For example, the turbine can also have a rotor with one or more blades, mounted on the turbine shaft, exhibiting the same characteristics as the pump rotor. Likewise, the turbine can include a concentric bypass channel and a bypass channel with a valve and a bypass channel, all identical in design and with the same properties as the corresponding elements of the turbine.

[0023] The identical design of the pump and turbine results in a uniform flow within the hydrodynamic converter, enabling optimal transmission of drive parameters such as speed, torque, and power. Furthermore, the use of identical components reduces manufacturing and maintenance costs.

[0024] The pump and turbine can be mounted facing each other, so that the pump outlet is opposite the turbine inlet and vice versa. This allows for a compact design of the hydrodynamic converter.

[0025] The hydrodynamic converter is used in a wind turbine to drive its generator.

[0026] The wind turbine comprises, in addition to the hydrodynamic converter, a tower having an upper and a lower end, at least one rotor located at the upper end of the tower and having one or more rotor blades and a rotor shaft, and a generator with a generator shaft. A pump shaft of the hydrodynamic converter's pump is mechanically connected to the rotor shaft of the wind turbine's rotor, and a turbine shaft of the hydrodynamic converter's turbine is mechanically connected to the generator shaft of the wind turbine's generator. The mechanical connections between the individual shafts can be implemented, for example, by means of suitable couplings, such as rigid couplings, flexible couplings, or articulated couplings. It is also possible for a gearbox, such as a mechanical gearbox, to be arranged between the rotor shaft and the pump shaft and / or between the turbine shaft and the generator shaft.

[0027] In one embodiment of the wind turbine, the generator can be located at the lower end of the tower. This embodiment is made possible by the transmission of drive forces via the hydrodynamic converter. In this case, the hydraulic connections between the pump and the turbine of the hydrodynamic converter can be of sufficient length to transmit the pump's drive forces via the turbine to the generator shaft. By arranging the generator at the lower end of the tower as described, the overall weight of the wind turbine components located at the upper end of the tower can be significantly reduced. This, in turn, increases the robustness and service life of the wind turbine.

[0028] In another embodiment of the wind turbine, two rotors can be arranged on a common rotor shaft at the top of the tower. For example, a first rotor can be located at one end and a second rotor at the opposite end of the rotor shaft. In this case, the mechanical connection between the pump shaft and the rotor shaft can be achieved, for example, by means of a gearbox, in particular a bevel gear gearbox, whose output shaft can be connected to the pump shaft. The attachment of a second rotor to the rotor shaft is made possible, in particular, by positioning the generator at the bottom of the tower, since this prevents the weight of the second rotor from exceeding a permissible total weight at the top of the tower. Brief description of the drawings

[0029] Figure 1Figure 1 shows a simplified schematic sectional view of a longitudinal section through a hydrodynamic converter with a pump and a turbine according to an embodiment of the invention. Figure 2 shows a simplified schematic cross-section through the in Figure 1 Pump of the hydrodynamic converter shown. Figure 3 shows a simplified spatial representation of a pump impeller that is in Figure 2 pump shown. Figure 4 Figure 1 shows a simplified schematic side view of a wind turbine according to an embodiment of the invention. Examples

[0030] Exemplary embodiments of the hydrodynamic converter and the wind turbine according to the invention are described in more detail below with reference to the figures. Identical or similar elements in the figures are designated with the same reference numerals. Therefore, repetitive descriptions are omitted where necessary.

[0031] An embodiment of the hydrodynamic converter is described below using the following example: Figures 1 to 3 describe.

[0032] All areas of the hydrodynamic converter that can be exposed to hydraulic fluid are in Figure 1 The area is characterized by dotted lines, and the flow direction of the hydraulic fluid is indicated by arrows. Likewise, the direction of rotation of the pump and turbine is shown. Figure 1 Each marked by an arrow.

[0033] The pump 1 comprises a pump shaft 23, which is connected to a rotor shaft of a wind turbine (in the Figures 1 to 3(not shown) is mechanically connectable. The pump shaft 23 is rigidly connected to a rotor 2, on the outside of which two vanes 3 are arranged at a distance of 180° from each other, which rotate in a housing 40 of the pump 1. The pump shaft 23 is supported in the housing 40 by means of two bearings 39, 33 (see Figure 2 The rotor 2 can, for example, be connected to the pump shaft by means of a conventional shaft-hub connection. It is also possible that the rotor 2 and the pump shaft 23 are manufactured as a single piece. The housing 40 is made in two parts and has a plurality of screw connections 31 on its outer circumference. In addition, sealing rings 35, 38 are attached to opposite end faces of the housing 40.

[0034] The impellers 3 of pump 1 point in the Figure 1The longitudinal section shown has the shape of a right-angled triangle. A rear side 47 of the blades 3 extends perpendicularly from the outside of the rotor 2 to an outer circumference of the housing 40, and a front side 41 of the blades 3 extends at an angle from the outside of the rotor 2 to an outer edge of the blade rear side 47, e.g., from a lowest point 42 to a highest point 44 of the blades 3 (see also Figure 3 ).

[0035] The housing 40 incorporates a bypass channel 4 and a sealing channel 29, which together form an annular, concentric channel 4, 29 arranged around the rotor 2 and the pump shaft 23, respectively. The pump 1, or rather its housing 40, also has an inlet 21 and an outlet 6, which are connected to each other by means of the bypass channel 4. The sealing channel 29 is located between the inlet 21 and the outlet 6 of the pump 1 and is closed by means of a valve 25. For this purpose, the valve 25 has a closing element 27, which in this case is designed as a closing cylinder 27 that closes a cross-section of the sealing channel 29. The bypass channel 4 has a circular arc shape with a central angle of 180°. In particular, the bypass channel 4 is arranged in the housing 40 parallel to a plane perpendicular to an axis of the pump shaft 23.

[0036] The diameter of the bypass channel 4 and the sealing channel 29 is essentially equal to the length of the rear surface 47 of the vanes 3, allowing them to extend radially outwards from the outside of the rotor 2 to convey the hydraulic fluid through the pump 1. There is only a minimal radial distance 37 between the outer edge or highest point 44 of the vanes 3 and the housing 40, which is necessary to prevent the vanes 3 from contacting the housing. Different boundary conditions at various operating points of the hydraulic converter can be taken into account when determining the required radial distance. In this way, pump leakage is minimized, thereby increasing its efficiency.

[0037] The valve 25 is opened by means of a vane 3 when it passes through the locking channel 29. The locking cylinder 27 of the valve 25 is thereby pushed by a stroke 26 from a closed position to an open position by the inclined front face 41 of the vane 3. While the valve 25 is open, the locking channel is closed by the vane 3, as it extends over a diameter of the locking channel 29. The valve 25 may include a compression spring (not shown), against whose spring force the vane 3 opens the valve 25 and which closes the valve 25 again as soon as the vane 3 has passed over the valve 25. Instead of a compression spring, the valve 25 may contain a solenoid for closing the valve 25 (not shown). In particular, the compression spring or the solenoid can act on the locking cylinder 27, pushing it into a position in which it closes the locking channel 29.

[0038] The valve 25 in the sealing channel 29 prevents hydraulic fluid located in the area of ​​the pump outlet 6 from flowing back to the pump inlet 21. This prevents a "short circuit" of the hydraulic fluid circulating in the pump 1. A section 29a of the sealing channel 29, located between the valve 25 and the pump outlet 6, is connected to the pump outlet 6 by means of a bypass channel 28. This allows hydraulic fluid located between the front face 41 of a vane 3 entering the sealing channel 29 and the closing element 27 of the valve 25 to be directed to the pump outlet 6. In this way, it is prevented that hydraulic fluid accumulates in the sealing channel 29 upstream of the valve 25 and thereby hinders or even completely prevents the rotation of the rotor 2.

[0039] Turbine 11 is identical in construction to pump 1 and comprises a turbine shaft 45, which is connected to a generator shaft of a generator of the wind turbine (in the Figures 1 to 3 (not shown) is mechanically connectable. The turbine shaft 45 is rigidly connected to a rotor 13, on the outside of which two blades 12 are arranged, rotating in a housing of the turbine 11. The turbine housing, as well as the bearing arrangement of the turbine shaft 45 and the design of the rotor 13 with the turbine blades 12, correspond to those in the Figures 2 and 3 Elements of pump 1 shown.

[0040] The turbine blades 12 point in the Figure 1The longitudinal section shown, analogous to the pump impellers 3, has the shape of a right-angled triangle and extends in the same way from the outside of the turbine rotor 13 to an outer circumference of the turbine housing. Likewise, the turbine 11 has a bypass channel 15 and a bypass channel 46, which together form an annular, concentric channel 15, 46 arranged around the rotor 13 and the turbine shaft 45, respectively. The bypass channel 15 of the turbine 11 also has a circular arc shape with a central angle of 180°. In particular, the bypass channel 15 is also arranged parallel to a plane perpendicular to an axis of the turbine shaft 45 in the turbine housing.

[0041] Furthermore, the turbine 11, or rather its housing, has an inlet 10 and an outlet 18, which are connected to each other by means of the bypass channel 15. Analogous to the arrangement in the pump 1, the sealing channel 46 of the turbine 11 is arranged between its inlet 10 and outlet 18 and is closed by means of a valve 8. The valve 8 is identical to the valve 25 in the sealing channel 29 of the pump 1 and contains a closing cylinder 30, which closes a cross-section of the sealing channel 46 of the turbine 11. Likewise, a section 46a of the sealing channel 46 is connected to the turbine outlet 18 by means of a bypass channel 19 to prevent a build-up of hydraulic fluid in front of the valve 8. The opening and closing of the closing cylinder 30 of the valve 8 is effected by the turbine vanes 12 as described above in connection with the pump 1, with the closing cylinder 30 performing the stroke 9.

[0042] The pump inlet 21 is connected to the turbine outlet 18 via a line 20 (second hydraulic connection 20), and the pump outlet 6 is connected to the turbine inlet 10 via a line 7 (first hydraulic connection 7). This allows the hydraulic fluid to circulate in a circuit between pump 1 and turbine 11. Pipes can also be used instead of lines 7 and 20. Pump 1 and turbine 11 are arranged facing each other, so that pump inlet 21 and turbine outlet 18, as well as pump outlet 6 and turbine inlet 10, are opposite each other. In this way, lines 20 and 7 form a direct connection between inlets 21 and 10 and outlets 6 and 18 of pump 1 and turbine 11, thus enabling a compact design of the hydrodynamic converter. Furthermore, the two lines 7 and 20 are of the same length, which supports a uniform flow of the hydraulic fluid in the hydrodynamic converter.

[0043] The pump inlet 21 is configured to introduce hydraulic fluid entering the pump 1 from line 20 (indicated by the arrow in front of the pump inlet 21) tangentially into the circulation channel 4, forming a circle concentric with the pump shaft 23. Similarly, the pump outlet 6 is configured to discharge the hydraulic fluid from the circulation channel 4 tangentially to the circle concentric with the pump shaft 23. Hydraulic fluid entering the circulation channel 4 tangentially through the pump inlet 21 impinges on the rear faces 47 of the impellers 3 located in the circulation channel 4, thus causing the rotor 2 and the pump shaft 23 to rotate in the direction of flow of the hydraulic fluid. After circulating in the circulation channel 4, the hydraulic fluid exits the pump 1 tangentially through the pump outlet 6.Furthermore, at this point, hydraulic fluid discharged from the pump 1 via the bypass channel 28 from section 29a of the barrier channel 29 is routed out (indicated by the arrows at the pump outlet 6).

[0044] In the Figure 1In the illustration shown, the rotor 2 is in a position where the rear surfaces 47 of the two pump vanes 3 extend in a horizontal direction. In this position of the rotor 2, it is particularly clear that the hydraulic fluid, upon entering and exiting the circulation channel 4, strikes the rear surfaces 47 of the pump vanes 3 perpendicularly, i.e., at an angle of 90°, and thus enters and exits the circulation channel tangentially. Due to the design of the rotor 2 with the pump vanes 3 and the circulation channel 4, the flow direction of the hydraulic fluid at every point in the circulation channel 4 is tangential to its circular arc shape; that is, the torque transmitted by the hydraulic fluid to the rotor 2 is constant during one revolution in the circulation channel 4 and acts tangentially on the rotor 2 at all times.In other words, the tangential effect exists at every point during the entire circulation of the hydraulic fluid in the circulation channel 4, which allows a high efficiency of the pump 1 to be achieved.

[0045] Similarly, the turbine inlet 10 is configured to introduce hydraulic fluid, which enters the turbine 11 from line 7 (indicated by the arrow in front of the turbine inlet 10), into the bypass channel 15 in a tangential direction concentric with the turbine shaft 45. Likewise, the turbine outlet 18 is configured to discharge the hydraulic fluid from the bypass channel 15 in a tangential direction concentric with the turbine shaft 45. Hydraulic fluid entering the bypass channel 15 tangentially through the turbine inlet 10 then strikes the rear faces 47 of the blades 3 located in the bypass channel 15, thus causing the rotor 13 and the turbine shaft 45 to rotate in the direction of flow of the hydraulic fluid. After circulating in the bypass channel 15, the hydraulic fluid exits the turbine 11 tangentially through the turbine outlet 18.Furthermore, at this point, hydraulic fluid diverted from section 46a of the sealing channel 46 is routed out of turbine 11 via bypass channel 28 (indicated by the arrows at turbine outlet 18). Due to the identical design of pump 1 and turbine 11, the torque transmitted by the hydraulic fluid to rotor 13 during one revolution in the bypass channel 15 remains constant and acts tangentially on rotor 2 at all times, thus ensuring a high efficiency for turbine 11. The identical design of pump 1 and turbine 11 also results in a uniform flow within the hydrodynamic converter, enabling optimal transmission of the drive parameters of speed, torque, and power. Moreover, the use of identical components reduces manufacturing and maintenance costs.

[0046] An embodiment of the wind turbine 100 according to the invention is described below using the following as an example. Figure 4 described.

[0047] The depicted wind turbine 100 comprises a tower 170, which has an upper and a lower end, and two rotors 110a, 110b, which are arranged at an upper end of the tower 170. The two rotors 110a, 110b are arranged at opposite ends of a common rotor shaft 120a and each has several rotor blades 160a, 160b, of which in Figure 4 Two are visible at a time.

[0048] The mounting of two rotors 110a, 110b on the rotor shaft 120a is made possible by the position of a generator 130 of the wind turbine 100, which is not connected to the rotor shaft 120a at the upper end of the tower 170 as is usual, but instead is arranged at its lower end. A generator shaft 130 of the generator is driven via a bevel gear 150 and a hydrodynamic converter, as described in the Figures 1 to 3 shown, driven by rotors 110a, 110b.

[0049] In particular, the bevel gear unit 150 and a hydrodynamic converter are arranged between the rotor shaft 120a and the generator shaft 140. The hydrodynamic converter is located in Figure 4 The pump 1 and the turbine 11 as well as the hydraulic connections 7, 20 between the pump 1 and the turbine are visible.

[0050] The bevel gear unit 150 comprises a first, unspecified crown gear arranged on the rotor shaft 120a, and a second, unspecified crown gear arranged on an output shaft 120b of the bevel gear unit 150, which is connected to a pump shaft (in Figure 4(not shown) is connected to the pump 1 of the hydrodynamic converter. A first, unspecified bevel gear engages in the first crown gear, which is connected by means of two unspecified shafts to a second, unspecified bevel gear, which in turn engages in the second crown gear. In this way, a rotary motion of the rotor shaft 120a can be transmitted to a pump shaft of the hydrodynamic converter, which in turn transmits this motion via the turbine 11 to the generator shaft 140. The output shaft 120b of the bevel gear unit 150 can, for example, be mechanically connected to the pump shaft of the hydraulic converter by means of a suitable coupling. Likewise, the turbine shaft (in Figure 4 (not shown) and the generator shaft is mechanically connected with a suitable coupling.

[0051] Due to the position of the generator 130 at the lower end of the tower 170, the hydraulic connections 7, 20 can be designed as pipes in this case to provide sufficient stability over the required length between pump 1 and turbine 11.

[0052] By arranging the generator at the lower end of the tower as described, the overall weight of the wind turbine components located at the upper end of the tower can be significantly reduced. This, in turn, increases the robustness and lifespan of the wind turbine. Furthermore, it allows for the attachment of a second rotor 110b to the rotor shaft 120a, since its additional weight does not cause the permissible total weight at the upper end of the tower 170 to be exceeded. Reference symbol list

[0053] 1 Pump 2 Pump rotor 3 Pump impeller 4 Pump bypass channel 5, 17 Filling port 6 Pump outlet 7 Connecting line pump to turbine 8 Turbine shut-off valve 9 Turbine shut-off valve closing element 10 Turbine inlet 11 Turbine 12 Impeller 13 Turbine rotor 15 Turbine bypass channel 18 Turbine outlet 19 Turbine bypass channel 20 Turbine to pump connecting line 21 Pump inlet 23 Pump shaft 25 Pump shut-off valve 26 Pump shut-off valve closing element 27 Pump shut-off valve closing element 28 Pump bypass channel 29 Pump shut-off channel 30 Turbine shut-off valve closing element 31 Turbine housing screw connection 33, 39 Turbine bearing 35, 38 Pump and turbine sealing rings 37 Impeller to housing distance 41 Impeller front 42 Lowest point Blade 44 highest point Blade 45 Turbine shaft 46 Turbine lock channel 47 Rear of blade 100 Wind turbine 110a, 110b Rotor Wind turbine 120a, 120b Rotor shaft Wind turbine 130 Generator 140 Drive shaft Generator 150 Gearbox 160a, 160b Rotor blade Wind turbine 170 Tower (170)

Claims

1. Hydrodynamic converter for a wind turbine (100), comprising: - a pump (1) with a pump shaft (23) which can be mechanically connected to a rotor shaft (120a) of the wind turbine (100); - a turbine (11) with a turbine shaft (45) which can be mechanically connected to a drive shaft (140) of a generator (130) and is fluidically connected to the pump (1), wherein the hydrodynamic converter is configured to circulate hydraulic fluid in a circuit between the pump (1) and the turbine (11) and thereby transmit drive quantities of the pump shaft (23) to the turbine shaft (45).

2. Hydrodynamic converter according to claim 1, wherein the pump (1) has a circulation channel (4) concentric to the pump shaft (23) which connects an inlet (21) and an outlet (6) of the pump (1), and a blocking channel (29) which is arranged between the inlet (21) and the outlet (6) of the pump (1) and is closed by means of a valve (25).

3. Hydrodynamic converter according to claim 2, wherein the inlet (21) of the pump (1) is configured to introduce the hydraulic fluid in a tangential direction to a circle concentric with the pump shaft (23) into the circulation channel (4), and the outlet (6) of the pump (1) is configured to discharge the hydraulic fluid out of the circulation channel (4) in a tangential direction to the circle concentric with the pump shaft (23).

4. Hydrodynamic converter according to claim 2 or 3, wherein a section (29a) of the barrier channel (29) which is arranged between the valve (25) and the outlet (6) of the pump (1) is connected to the outlet (6) of the pump (1) by means of a bypass channel (28).

5. Hydrodynamic converter according to any one of the preceding claims 2 to 4, wherein the pump (1) has a rotor (2) arranged on the pump shaft (23) and on the outside of which one or more vanes (3) are attached.

6. Hydrodynamic converter according to claim 5, wherein a rear side (47) of each wing (3) extends radially outwards perpendicular to the outside of the rotor (2) and a front side (41) of each wing (3) extends at an angle of inclination from the outside of the rotor (2) to an outer edge of the rear side (47).

7. Hydrodynamic converter claim 6, wherein a diameter of the bypass channel (4) and a diameter of the barrier channel (29) is substantially equal to a length of the rear side (47) of the vanes (3).

8. Hydrodynamic converter according to one of claims 5 to 7, wherein each vane (3) is configured to open the valve (25) when a vane (3) passes through the barrier channel (29).

9. Hydrodynamic converter according to one of the preceding claims, wherein the turbine (11) is of the same design as the pump (1).

10. Hydrodynamic converter according to one of claims 2 to 9, wherein a first hydraulic connection (7) is arranged between the outlet (6) of the pump (1) and the inlet (10) of the turbine (11) and a second hydraulic connection (20) is arranged between the outlet (18) of the turbine (11) and the inlet (21) of the pump (1).

11. Use of a hydrodynamic converter according to one of claims 1 to 10 for driving a generator (130) in a wind turbine (100).

12. Wind turbine (100) comprising: - a tower (170) having an upper and a lower end; - at least one rotor (110a, 110b) arranged at an upper end of the tower (170) having one or more rotor blades (160a, 160b) and a rotor shaft (120a); - a generator (130) with a generator shaft (140); and - a hydrodynamic converter according to at least one of claims 1 to 9, wherein a pump shaft (23) of a pump (1) of the hydrodynamic converter is mechanically connected to the rotor shaft (120a) and a turbine shaft (45) of a turbine (11) of the hydrodynamic converter is mechanically connected to the generator shaft (140).

13. Wind power plant (100) according to claim 11, wherein the generator (130) is arranged at a lower end of the tower (170).

14. Wind power plant (100) according to claim 11 or 12, wherein two rotors (110a, 110b) are arranged on a common rotor shaft (120a) at the upper end of the tower (170).

Images